Within the last month a thorough laser treatment has been performed to a painted panel by the research groups of the Photonics for Cultural Heritage activity of IESL-FORTH. The painting, which was “excavated” from the storage of the conservation laboratories of the National Gallery in London, is traveling around Europe in order to be examined by the latest developments in instrumentation and methodologies as regards scientific conservation of Cultural Heritage assets. The round robin involves 5 laboratories, which within the WP9 of the CHARISMA EU FP7 project, will analyse and document this fairly old (17/18^th century) painting prior and after its laser cleaning. The painting, depicting a battle scene, has undergone a series of previous unsuccessful conservation interventions and thus is a real challenge for the conservation scientists. Spectral imaging, evaluation of its structural integrity and elemental analysis of its paint components were performed, in order to study the preservation condition of the painting prior and after its laser treatment. This intervention involves the use of UV laser irradiation for the elimination of the outermost varnish layers of the painting in a gradual and controlled way. A number of varnish layers of different composition and ageing were detected and laser cleaning managed to expose safely a healthy surface. The painting continues its trip around Europe, expecting a thorough restoration methodology as the outcome of this “scientific” adventure.